On 1/20/11 10:58 AM, Chuck Landress wrote:
<<SNIP>> I recently worked on a system where the original
programmers included only the fields they needed when they wrote
programs. They ended up with a LOT of logical files with the same
keys but different fields. It was a real mess. <<SNIP>>

The database by default will effect "sharing" an access path of one logical file with all of the other logical files with the "same keys". Logical independence from the physical definition is exactly why one would want to create multiple LF, each with its own format(s) that are specific to a [set of] program[s]. The concept being fully understood, can be applied as a powerful means of limiting the effect of change on applications, just as using SQL instead of RLA; applied poorly, either can be just as hard to manage as the other.

Regards, Chuck

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